Method of corner construction



April 24, 1956 A, T. KUNK METHOD OF CORNER CONSTRUCTION Filed March 31, 1955 INVENTOR. ALOYSIUS T. KUNKEL ATTORNEY United States Patent METHOD OF CORNER CONSTRUCTION Aloysius T. Kunkel, Akron, ohm

Application March 31, 1955, Serial No. 498,31

2 Claims. (Cl. 29-411 reinforced by steel or other rigid reinforcing members of various types.

With the advent of aluminum and other types of metal sash, the method of corner construction remained substantially the same, with mitered corners being reinforced at their respective points of juncture with steel or other structural supports that were welded or otherwise secured in place, to retain the respective frame members in their right angle condition with respect to each other. In the great majority of applications of metallic sash construction, the frame members take the form of flat, thin wall extrusions, shaped as angles or other formed configurations, to add rigidity to this relatively light type of material. Because of the thin wall section of the stock material employed, it has been difiicult to obtain a strong welded corner joint that would wishstand the Wear incident to normal usage. Additionally, where weldinghas been employed in such cases to secure the frames with respect to each other at the corners, it has been found that the appearance of the welding marks on the exterior surface of the sash is detrimental to the saleofthe ultimate product. As a result of the aforementioned difficulties, the manufacturers of metallic sash, and particularly aluminum sash, have been forced, in the majority of cases, to resort to the use of concealed reinforcing members having gripping or locking means of intricate, and accordingly expensive, design.

Heretofore, it has not been considered practical to employ hollow extrusions as frame members, due to the increased cost of the same over the usual flat formed extrusions. However, in addition to providing a stronger corner joint in the manner to be taught by this inventor, the same are advantageous in that they-provide a point of support for a second pane of glass, that is known as a storm window.

Recently, research in the field of sash construction has been directed toward the use of certain non-metallic extrusions as sash frame members because of the insulation properties of the same. While initial developments in this direction have indicated that such sash is highly desirable because of the aforementioned insulation properties, it has been found as a practical matter, that sufiicient corner reinforcing cannot be incorporated at the present time into such sash because of the previously discussed difliculties encountered in the joining of thin wall corner sections.

Accordingly, it is one object of this invention to provide an improved method of reinforcing corners of sash,

that can be employed with equal utility in metallic or non-metalic sash members.

It is a further object of this invention to provide a method of reinforcing the corners of sash without the use of welding, brazing or soldering.

It is a still further object of this invention to provide a method of reinforcing sash corners that is characterized by the use of internal reinforcing supports of simplified,

design and construction.

' It is a still further object of this invention to provide a method of reinforcing the corner construction of nonmetallic sash units in a simple and highly efficient manner.

These and other objects of the invention will become more apparent upon a reading of the following brief specification, considered and interpreted in the light of the accompanying drawings.

Of the drawings:

Figure l is a perspective View, partly broken away and in section, illustrating schematically a window sash constructed in accordance with the improved method of this invention.

Figure 2 is a section of a typical reinforcing insert taken on the lines 22 of Figure l.

Figure 3 is a view taken on the lines 33 of Figure l.

Figure 4 is a perspective view illustrating one improved insert for corner reinforcement.

Figure 5 is a perspective view illustrating the extrusion from which the reinforcing inserts are obtained.

In order to best understand the preferred method of practicing the invention for constructing a sash unit having reinforced corners, attention is directed to Figure l of the drawings, wherein a sash S is schematically illustrated in perspective view.

The sashS includes a plurality of frame members 10, 11, 12 and 13, that are joined together at their respective ends by reinforcing inserts 14, 14 to define a rectangular unit; the arrangement being such that one said insert 14 is positioned interiorly of the point of juncture between each set of adjoining frame members, in a manner to be described.

To this end, each frame member, 10, 11, 12 and 13 is shown as being of elongated, rectangular configuration,

so as to define a hollow body capable of being extruded in known manner. Considering first the member 11, the same is, for the purposes of this specification, assumed to be equal to the crosssectional dimensions-of the frame member 13; while the frame member 10, although different in cross-sectional dimension from the frame members 11 and 13, is similar to the cross-sectional dimensions of the frame member 12. Accordingly, the frame members 10 and 12 will hereinafter be referred to as the top and bottom frame members, respectively; while the frame members 11 and 13 will hereinafter be designated as side frame members.

Considering first the'side frame members 11 and 13, .it will be noted that each of the same has the interior thereof defined by an internal rectangular cavity of width X and depthY (see Figure 1); while the top and bottom members 10 and 12 each have a vertical height Z, as well as a horizontal depth Y that is equal in dimension to the dimension Y of the members 11 and 13. In this manner, the four side members 10, 11, 12 and 13, while possessing the same depth, as defined by the dimension Y, are characterized by the fact that the top and bottom frame members have a vertical height (dimension Z) that is greater in dimension than the width dimension (dimension X) of the side frame members 11 and 13.

Referring now to Figures 4 and 5 of the drawings, it will be seen that each insert 14 is of L-shaped configuration so as to define leg members 14a, 14b of substantially equal length, with the leg 14a having a cross-sectional height corresponding to the dimension Z of the top and j 3 bottom frames 10 and 12; while the width thereof corresponds to the dimension Y. By like token, the crosssectional width of the leg 14b is shown as being the same as the dimension X of the side .frame members ll and 13; while the width thereof is equal 'to the width of the leg 14a, namely, width Y above described.

In this manner, the leg 14b can be fitted interiorly of either side frame member 11 or 13; while the leg 14a can be similarly fitted into either open axial end of the frame members 10 or 12.

As best shown in Figure of the drawings, the individual inserts 14, 14 are obtained by first providing an L'shaped extrusion that is generally designated as 20. This extrusion 20 has the dimensions of the respective legs 20a, 20b thereof corresponding respectively to the dimensions of the legs 14a and 14b of the individual insert 14; and accordingly, when it is desired to produce a given number of inserts, it is merely necessary to mark a length longitudinally of the extrusion 20 corresponding in length to the dimension Y, and remove, as by sawing or cutting, a segment of the extrusion 20. Upon removal, this segment will have the approximate dimensions shown in Figure 4 of the drawings; with the result that the same can be positioned interiorly of adjacent frame members in a manner to be described.

In this regard, it is to be understood that all of the members 10, 11, 12 and 13 are shown as having mitered edge portions 11a, 12a, 13a and 14a, respectively, that permit the joining of these members together at right angles, as shown in Figure 1 of the drawings.

In use of the improved process for building a window sash of the form shown in Figure 1, for example, the user first determines the size of top, bottom and side frame members that will be employed as component elements of the sash unit. With the exterior size of these respective frames determined, the manufacturer next determines the vertical height (dimension Z) of the internal cavity in the top and bottom rail members and 12, for example. Additionally, at this time the horizontal width (dimension X) of the internal cavity in the side frame members 11 and 13 is determined in like manner; it being understood that the depth of all four members 10, 11, 12 and 13, as represented by the dimension Y, will be the same, it being standard practice to make the depth of all four frame members the same in one unit of sash construction.

With the above dimensions in mind, the user may design and subsequently produce an L-shaped extrusion of considerable longitudinal length. The height and width respectively, of the leg members a and 20b can be determined by consideration of the dimensions Z and X, respectively. with the dimension Z determining the height of the leg 20a, while the dimension X deter mines the width of the leg 2011 (see Figure 5). The dimensions L and L1 indicated the length of projection interiorly of the frame members upon insertion, and are, of course, optional and may or may not, as desired, be equal. Upon obtaining an extrusion made to the dimensions previously determined, the user may then sever successive lengths represented by the dimension Y from the extrusion 20, to thus obtain a three-dimensional corner insert 14 that will be capable of being snugly and firmly received interiorly of adjoining frame members.

After the frame members have been provided with the appropriate miters 10a, 11a, 12a and 13a on the axial ends thereof to permit right angle abutment with an adjoining frame member, the user may then insert the leg 14a of an insert 14 into one axial end of the frame member 10, by matching up the dimensions Z and Y of the leg 14a, with the dimensions Z and Y of frame 10, and then inserting the leg 14a into the open end of the frame 10 to a depth L. This procedure will be repeated on the opposite axial end of the frame member 10 with a second insert 14, with the result that the frame member 10 will have two inserts 14, 14 firmly positioned interiorly of the opposed axial ends thereof. At this point,

the frame member 13 may be positioned over the project'ing leg 14b of the insert '14 that is carried by frame 10, while the frame member 11 may similarly be positioned over the leg 14b of the insert 14 that is carried in the opposite end of the frame member 10. At this point, the legs 14a, 14a of two additional inserts 14, 14 may be positioned interiorly of the opposed ends of the frame member 12, as previously described, and with the inserts thus assembled interiorly of the opposed ends of the frame member 12, this sub-assembly may then be positioned interiorly of the free ends of the frame members 11 and 13, with the result that the entire unit is now assembled.

It will be understood that in each of the preceding sub-assemblies each insert 14 is moved to its full depth of penetration with the respective frame member attached thereto, with the result that the mitered edges of the frame members will abut with each other to com pletely conceal the reinforcing inserts 14, 14 while defining a rectangular unit having an aesthetic external appearance.

It will be noted that by using a pre-engineered insert, a snug fit will be obtained between the inserts and the frame members that the same interconnect, and accordingly, the overall sash unit, when assembled will be rigid and not susceptible to being affected by the application of torsional or other forces. It will be further noted that the close tolerance or fit that exists between the inserts and the frame members, operates to provide an overall sash unit possessing the inherent rigidity of the individual inserts, with the result that the overall sash will be characterized by exceptional rigidity.

It is apparent that deviations in the tolerance of the window frame members 10, 11, 12 and 13 could be compensated for by chamfering the legs 20a and 20b, as at 21, 22, respectively (see Figure 5) to thus enable the inserts to be forced into the frames in the event the frames are slightly undersized. As an alternate solution, either leg of the extrusion could, if desired, be tapered in crosssection to achieve a similar result.

It will also be seen that in the event that the windows of different dimensions are to be made, it would be a simple matter to re-design the height and width dimensions of the leg members defining the extrusion 20 so that a new extrusion could be simply and efficiently provided without the replacement of expensive dies, molds and other equipment of this nature.

In the preceding specfication, the frame members have not been limited in the disclosure to being of metallic or non-metallic material, it being apparent that either metallic or non-metallic material could be used with equal result, due to the fact that the material of the frame members, when connected through the medium of the rigid reinforcing inserts, assumes the overall rigidity of the insert members per se. Similarly, the material and shape of the reinforcing inserts could be varied, within limits, to meet changing requirements in known manner.

By like token, the method of this invention is not limited to use with the preferred hollow rectangular mernber previously shown and described, it being apparent that the method could be employed with any type frame member. Additionally, it is to be understood that the method of this invention is not limited to use in sash construction, it being apparent that the method could be utilized for reinforcing other types of corner construction without the exercise of invention.

Accordingly, modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

l. A method of sash construction, comprising the steps of; determining the internal cross-sectional dimensions of adjoining hollow members; extruding an L-shaped member having the thickness of the respective leg portions thereof approximating the coplanar height and width a length of said extruded member into an insert piece having its severed length dimension corresponding to the cross sectional coplanar depth dimension of said adjoining hollow member; roughening the planar surfaces of said insert created by said severing action; inserting one said frame member over the appropriate free edge of said leg member of said severed insert; inserting the other said frame member over the free edge of said remaining leg of said insert; and moving said frame members axially of said leg members into abutting relationship with each other.

2. A method of sash construction, comprising the steps of; determining the internal cross-sectional dimensions of adjoining hollow frame members; extruding an L-shaped member having the thickness of the respective leg portions thereof approximating the coplanar height and width dimensions of said adjoining frame members; severing a length of said extruded member into an insert I piece having its severed length dimension corresponding to the cross-sectional coplanar depth dimension of said adjoining hollow members; relieving a sharp corner of at least one leg portion at the free edge thereof, whereby the free end dimensions of said relieved leg portion are reduced; inserting one said frame member over the appropriate free edge of said leg of said severed insert; inserting the other said frame member over the free edge of said remaining leg member of said insert; and moving said frame members axially of said leg members into abutting relationshipwith each other.

References Cited in the file of this patent UNITED STATES PATENTS 1,823,009 Toaz Sept. 15, 1931 1,860,005 Baldwin, Jr May 31, 1932 2,464,514 Kaufmann Mar. 15, 1949 2,726,437 Taylor Dec. 13, 1953 

